When a user browses the Internet using a browser on a computer, the user builds up an Internet context for her browsing activity, e.g., through cookies, history and personalized data. As the popularity of Internet browsing has grown, it is not uncommon to have more than one person using a single computer. When different people use the same computer for Internet browsing, Internet contexts can become confused. As a result, one user may no longer know which websites he has visited, and users' preferences for the same website may conflict.
To accommodate multi-user arrangements, operating systems support “profiles” for different users, each profile defining a particular work environment configured for a particular user. Each user of a computer can maintain his or her own profile, which accommodates the particular user. However, switching from one Internet context to another requires a system-wide process shutdown, meaning that a current user must end any tasks that are in progress and log off before a new user can log in. In addition, most families do not go to the trouble to enable profiles on their home computers and, therefore, they cannot switch contexts at all.